Dwarf Planets

Scientists have discovered a ring system around the dwarf planet Haumea.

The dwarf planet 2007 OR10, informally known as "Snow White," has a moon that's between 150 miles and 250 miles (240 to 400 kilometers) wide, a new study reveals.

The dwarf planet Ceres shines and spins in a new video captured by NASA's Dawn spacecraft.

NASA's Dawn spacecraft has lost another orientation-maintaining reaction wheel, but the failure doesn't threaten the probe's continuing work at the dwarf planet Ceres, agency officials said.

New observations reveal that the far-flung object 2014 UZ224 (informally known as DeeDee, for "Distant Dwarf") is about 395 miles (635 kilometers) wide — big enough to claim "dwarf planet" status.

The only mountain on Ceres may slowly disappear over a few hundred million years, spreading out like honey on a plate.

Pluto's status as a "dwarf planet" is once again stirring debate. This comes as some planetary scientists are trying to have Pluto reclassified as a planet – a wish that's not likely to come true.

The location of newfound water-ice deposits on Ceres are linked to wild swings in the dwarf planet's tilt over the eons, a new study suggests.

On the dwarf planet Ceres, volcanoes rage — but instead of hot lava coming out of them as on Earth, they spew brine and ice.